1. Field of the Invention
This invention relates to apparatus for effecting a starting pull upon the rope of a recoil-start type internal combustion engine.
2. Description of the Prior Art
Small internal combustion engines in the range of 2-10 horsepower are commonly used upon various types of wheeled machines such as lawn mowers, snow blowers, roto-tillers, edgers, cement mixers, generators, air compressors, etc. Such engines typically consist of one or two cylinders and may have an output shaft oriented in either horizontal or vertical disposition.
Numerous starter devices for small engines have been disclosed in the prior art. For example, electric starter motors have been adapted to crank small engines. However, electric starters are expensive and require considerable maintenance. Various auxiliary starters have been employed in attempts to aid in the starting of stubborn engines. For example, U.S. Pat. No. 4,569,315 to Bodnar discloses an electric drill operated device adapted to engage a shaft associated with a small engine. Such devices are of limited adaptability with respect to various engine designs. The benefits of using such devices are diminished because of the measures needed to adapt the starting device to the requirements of the engine.
Crank-spring type starters such as disclosed by U.S. Pat. No. 4,716,868 to Reuter have been disclosed. Such starters store mechanical energy from a hand crank, said energy being subsequently released by a rachet and pawl. Starters of this type are prone to mechanical failure and therefore are seldom installed upon modern small engines.
The vast majority of small engines currently produced are adapted with a rope-pull-recoil starter such as disclosed in U.S. Pat. No. 4,850,233 to Ishigo. Recoil rope starters utilize a rope wound upon a spool by a recoil spring. The spool is usually geared for mechanical advantage to a clutch which engages an input shaft. The force exerted by a pull upon the rope causes engagement of the clutch, producing rotation of the spool and input shaft, which in turn cycle the engine in order to start it. Upon release of force upon the rope, it is recoiled upon the spool by a recoil spring.
Recoil starting devices having either vertical or horizontal pull strokes have been disclosed. Devices requiring a vertical pull generally utilize the force of gravity to stabilize the machine while the rope is pulled. Often the weight of the machine is great enough to overcome the resistance to the rope pull exerted by the engine cylinder compression upon starting. Some machines are adapted to be stepped upon while starting to further stabilize the machine and provide greater starting force by the person pulling the rope.
However, machines which have a horizontal-pull rope starter and are mounted upon wheels absolutely require that the person starting the machine steps upon the machine to stabilize it. The nature of the horizontal pull while stepping upon the machine is often awkward, and requires the person starting the machine to rotate the torso while bending over. This maneuver has been known to cause serious back injuries, and is difficult for back sufferers and elderly persons to perform, particularly with a stubborn starting machine requiring numerous pulls. The problem is particularly experienced by those performing this starting motion often, such as repairmen and landscapers.
It is therefore an object of the present invention to provide an auxiliary starting device for horizontal rope-pull-start engines associated with small machines.
It is another object of the present invention to provide a starting device of the aforesaid nature which is easily adaptable to a variety of engines, requiring no modification of the machine.
It is a further object of this invention to provide a starting device of the aforesaid nature capable of immobilizing the machine against pulling force applied to the rope starter of the engine.
It is yet another object of this invention to provide a device of the aforesaid nature which is easily disengaged subsequent to starting.
Still other objects of this invention are to provide a device of the aforesaid nature which is simple to use, easily maintained, durable, and amenable to low cost manufacture.
These and other beneficial objects and advantages will be apparent from the following description.